Grinding Noise/Feeling When braking, brakes new

[Zoro]

I've got about 8K miles on brand new pads and rotors on my 90 XJ and when I stop I can hear this God awful grinding noise coming from up front, I did a visual on the pads& rotors and they look like they've got extremely little wear on them at all. This only happens when when braking and it's not the noise from sitting or warped rotors...Any ideas?

[Jess]

make sure you have the correct pads and the outer one is properly in position and not contacting the hub of the rotor.

[87manche]

you've got new pads and rotors, what about the drums and shoes out back?

[johnnyc]

Well, Zoro says he's got 8K miles on the pads and rotors, so I don't think that's the problem.

Check your hub assemblies. They make an awful racket when they go bad.

[Zoro]

Well, Zoro says he's got 8K miles on the pads and rotors, so I don't think that's the problem.

Check your hub assemblies. They make an awful racket when they go bad.
How would I go about checking them? I wouldn't be surprised if they're bad...

[AlohaBra]

Did you grease the sliders? Are they worn or grooved?

Take them apart and see.

[Robs92XJ]

I've got about 8K miles on brand new pads and rotors on my 90 XJ and when I stop I can hear this God awful grinding noise coming from up front, I did a visual on the pads& rotors and they look like they've got extremely little wear on them at all. This only happens when when braking and it's not the noise from sitting or warped rotors...Any ideas?

From up front? Seized caliper, probably. All the damage occurs to the inside of the rotor; the outboard pad and rotor will look like new. Take off the wheels and calipers, pull off the rotor and have a look at the inboard side. When my caliper froze, there was nothing left of the inboard brake pad, and so the rivets on the backing of the pad were having their way with the rotor.

If thats the case, you'll need to get 2 new calipers, 2 new rotors, and new pads, to keep everything even from side to side. Luckily all this stuff can be had for pretty cheap. I'd replace the brake fluid while you're at it, too.

Hope this helps- Rob

[Zoro]

Thanks.

Aloha Bra-Which sliders are you reffering to? The ones for the pads on the caliper?

What size socket takes off the caliper on a 90? I used a friend's tools to install the brakes & don't have a 12 pt socket that small. 5/16ths 12 pt IIRC, right?

[AlohaBra]

I meant where the pads slides, which I think are on the bracket.

But you also brought to mind the pins that the caliper slides on.

The sockets you are talking about are called Torx and are metric and labled t-10, t-20, t-30, etc.. You can get a whole set for like $15 nowadays. They are used all over the Jeep...like the seat track...suspensions...brakes...etc.

Also...the post above mine here...mentioned caliper seizing which could be the pin or the piston...so start by inspecting both sides. Once you have the brakes and wheel off...you can check the hubs.

EDIT.....sorry on the early model they might not be Torx..

[ready to mud]

mine does the exact same thing. my hubs are also brand new.

[87manche]

Thanks.

Aloha Bra-Which sliders are you reffering to? The ones for the pads on the caliper?

What size socket takes off the caliper on a 90? I used a friend's tools to install the brakes & don't have a 12 pt socket that small. 5/16ths 12 pt IIRC, right?
a 90 should have a 7mm allen head.
my frankenstein d30 has 90 knuckles on it.

[Zoro]

Turns out it was a 5/16" 12 pt socket.

Also it looks like when I got my inspection done somebody did a switcharoo on my brake pads. I installed Hawk pads that were BLUE frames and the ones I pulled off were just regular pads, black frames...Ate the crap outa my drilled & slotted rotor but thankfully it was only on one side, will be calling the stealership tomorrow.

[Tally_XJ]

Jesus! You got royally screwed. Its hard to believe there are people who would do something like this.

[AlohaBra]

WOW..that is appalling...I used to work in stealerships...but never had the balls to do that....steal brake pads...

In f...rig....ing ..credible....

[Robs92XJ]

Turns out it was a 5/16" 12 pt socket.

Also it looks like when I got my inspection done somebody did a switcharoo on my brake pads. I installed Hawk pads that were BLUE frames and the ones I pulled off were just regular pads, black frames...Ate the crap outa my drilled & slotted rotor but thankfully it was only on one side, will be calling the stealership tomorrow.

Wow that sucks...

Were the regular pads put on both the passenger and driver sides? The rotor that got fubar'ed, was it only eaten up on the inside face? If so, I think you still have problems besides the cheap pads. Were you succesfully able to push in the caliper piston (on the problem side) using a c-clamp, or was it substantially more difficult than the other side?

I guess the inspection guy may have put a heavily worn pad on the inside face but a less worn one on the outside, which would eventually cause this type of problem. Otherwise this sounds exactly like a seized caliper.

If it were me, I'd probably replace the calipers along with your pads and rotors at least as preventative maintenance since you're going to be in there anyways. If you don't, then I would suggest pulling off the wheel every week for the first few weeks and inspecting the pads to make sure the inside and outside pads are wearing evenly.

-Rob

[Zoro]

Both pistons went in easily and both pairs of pads were taken, called the stealership and they will be picking up my truck tomorrow...